EP2010399A2

EP2010399A2 - Id card comprising a contoured relief structure, and corresponding production method

Info

Publication number: EP2010399A2
Application number: EP07724160A
Authority: EP
Inventors: Markus Erdmann; Günter Endres
Original assignee: Giesecke and Devrient GmbH
Current assignee: Giesecke and Devrient GmbH
Priority date: 2006-04-13
Filing date: 2007-04-11
Publication date: 2009-01-07
Anticipated expiration: 2027-04-11
Also published as: EP2010399B1; CN101472745A; CA2648995A1; CN101472745B; DE102006055787A1; CA2648995C; WO2007118654A2; WO2007118654A3; US20090134618A1; US8181993B2

Abstract

Disclosed is an ID card which is made of plastic, e.g. PVC or polyester, and in which tactile symbols are clearly visible in the form of expanded relief structures (8). The symbols are bordered by a contour (9) which is created by coloring the plastic.

Description

ID card with contoured relief structure and corresponding manufacturing process

The invention relates to an identity card, in which symbols such as alphanumeric characters, patterns, images or the like, are designed in relief, and a method for producing a badge with a relief structure.

ID cards are used in many areas. For example, they are used as credit cards, bank cards, bank cards and the like in cashless payment. Provided with appropriate identification features, they can also be used as identification cards for their owner. On the one hand, because of their widespread use, they are typical mass-produced articles, that is, their manufacture must be simple and inexpensive, but on the other hand they must be designed to be as much protected against counterfeiting and falsification as possible. In addition, the data stored on them should be easy and secure for both machines and people.

ID cards are known in which information in the form of relief-like characters are imprinted on the card. On the one hand, the relief-like signs can be felt by humans, on the other hand they can also serve as a printing block to transfer the information from the card to paper.

From EP 308 904 it is known to provide a card, which can be made of PVC, among other things, by surface treatment with different features by differently guided laser processing. described In particular, the application of foamed embossing marks in surface plateaus, the application of flat characters on a card surface by discoloration and the application of visually verifiable authenticity features on a card surface. By using a two-layered card surface material whose cover layer is transparent, it is also possible to cause foaming and discoloration at the same time. However, the production of such two-layered card surfaces increases the overall card manufacturing effort.

From GB 2057363 A and EP 0469982 Bl further proposals are known to create relief structures in plastic, which are different in color from the border. According to GB 2 057 363 A, a special plastic based on a flocked foam is used for this purpose; According to EP 0469 982 B1, the foaming of a cast plastic should automatically bring about a color change. The former solution is too expensive for identity cards, the latter provides only small and hardly controllable color differences.

From DE 32 13 315 Al is known to produce tactile characters by foaming card material by means of a laser. An ID card consists of a plastic material or is provided with a surface layer of a plastic material which is mixed with chemical or physical blowing agents. By a laser beam, the plastic layer is heated locally and foamed. The locally foamed areas form a relief structure on the card surface.

From EP 1 113 131 A2 it is known to produce tactile characters by embossing and then to blacken the raised embossments with a laser. In particular, the blackening can be exactly on the surveys, so that a positive writing arises, or be made in between, so that a negative writing arises. Due to the blackness, the relief-like embossed tactile signs are also visually perceptible.

When trying to use the two aforementioned techniques together for the production of ID cards, it has been found that can not blackened with the laser foamed characters of a relief structure readily in a subsequent step with a laser or that areas of a badge that with blackened a laser, at least partially lose their darkness during subsequent foaming by means of a laser. It has not yet been possible to produce tactile blackened characters by lasers on cost-effective standard white plastic material such as polyester or PVC. Such characters could only be generated if the surface of the badge had previously been specially prepared, for example by the addition of carbon. Such preparation, however, adds to the cost of materials and degrades the visual appearance of the badge because of the formation of a gray haze on its surface. In addition, it has been found that the addition of carbon changes the physical properties of the card material, which may require a laborious testing and acceptance procedure.

The object of the present invention is therefore to propose an identification card with a relief structure made of foamed plastic and a method for its manufacture, in which the relief structure is visually easily recognizable.

This task is performed by an identification card as well as by a procedure for producing a Ausweiskarte with the characteristics of the sibling Claims solved. In dependent claims advantageous embodiments and developments of the invention are given.

An identity card according to the invention has a card surface with a relief structure made of foamed plastic. The relief structure can represent tactile symbols in the form of alphanumeric characters, patterns, images or other graphic structures.

The identification card can consist overall of a plastic which can be foamed locally by supplying energy, for example by irradiation with a laser beam. The foamable plastic may, for example, be mixed with chemical or physical blowing agents. Suitable plastics are listed for example in DE-OS 24 50 948, DE-AS 26 50216, DE-AS 2921 011 and DE-OS 3213 315.

Alternatively, the ID card can also have only one card surface a layer of foamable plastic, over the entire surface or only locally.

The identity card according to the invention is characterized in that the relief structure forming the symbols is bounded by a contour of discolored plastic. In other words, an area of discolored plastic is located adjacent to the relief structure in a non-foamed, flat area of the card surface.

The term "discoloration" or "discolored plastic" is understood here to mean that the card surface is specifically discolored, in particular darkened, by suitable treatment, for example by irradiation with a laser, in comparison to surrounding, untreated areas of the card surface. The "discolored" areas may be black or they may merely have a different color or gray shade than the untreated areas.

The contour of discolored plastic can be directly adjacent to the relief structure. Alternatively, between the relief structure and the contour made of discolored plastic there may be a narrow area of undyed, unaufschuftäumtem plastic.

Since, according to the invention, the relief structure of foamed plastic does not need to be discolored on its own, but only in an unfoamed area of the card surface is a contour of discolored plastic provided, the problem of discoloring foamed plastic may have to be avoided. The contour of discolored plastic, the relief structure, which in turn is preferably not discolored, optically well visible. Thus, an identification card is provided in which a relief structure is tactile as well as visually easy to perceive.

The relief structure needs to be partially bounded by the contour of discolored plastic. It is sufficient for an improved visual recognition already that each relief structure area is bordered only on one side of the discolored contour. This results in an optical impression of a shadow in oblique lighting.

Preferably, however, the contour completely surrounds the relief structure. That is, each self-contained relief texture area, such as each letter or number, is completely enclosed by the contour. In this way, a very good visual perception is ensured from different viewing angles. Preferably, the contour has a uniform width. In the case of relief structures with a size of a few millimeters, as is customary in ID cards, for example, a contour can be formed from a line surrounding the relief structure with a uniform width of a few hundred micrometers. Due to the uniform width of the contour results in a uniform, well-perceived and pleasant for the viewer appearance of the contour.

The card surface may be made of a single plastic material which may be in a foamed state as well as a discolored state. Which of these states the plastic material takes depends on the processing of the plastic material, as described below. As a plastic material are inexpensive and easy to process materials such as PVC or polyester, ABS or mixtures thereof into consideration. In addition, however, relatively expensive materials such as polycarbonate or mixtures of expensive and inexpensive materials, such as polycarbonate with PET / PETG, can be used.

The inventive method for producing a badge card assumes that the badge has a plastic material which can be foamed on the one hand by introducing energy, i. increases its volume, and on the other hand, if the energy is supplied in a different way, can change its color, for example, by setting a blackening of the plastic material.

The method according to the invention is particularly suitable for producing the identity card according to the invention and realizing its optional features described above. The method according to the invention comprises two steps: on the surface of the identification card, a foamed relief structure is formed by introducing energy in a first energy supply mode in foaming regions in a first manner; discolored contours are created around the foaming regions by introducing energy in a second energy delivery mode in a second manner.

The energy is preferably supplied by irradiation with a laser beam. The laser emitting laser may be suitably operated in various ways and with different power settings to enable different energy delivery modes. Suitably, the laser can work in particular (quasi) continuously (cw operation) or clocked. The respective energy supplied by the laser can also be influenced by adjusting the power of the laser beam, the wavelength and frequency of the laser light, the residence time of the laser beam on a surface area of the card to be treated and / or the focusing of the laser beam.

The steps of creating the frothed relief structure and creating the discolored contours may be performed in any order. For example, first the relief structure can be foamed and subsequently the discolored contours can be created around the relief structure. Alternatively, the discolored contours can first be generated and then the relief structure can be foamed in the areas bordered by the contours. Preferably, during the production of the discolored contours, the regions to be foamed or the already foamed relief structure are not irradiated with the laser beam. The contours can be formed as continuous, uniformly wide contour lines around the foaming areas around. By avoiding that the laser beam also irradiates the foaming areas to produce the discolored contours, it is possible to prevent the discolored contours at their transition to the foaming areas from having an irregular, frayed boundary which disturbs the visual appearance of the contours.

Such a frayed boundary may result in an alternative embodiment of the method according to the invention, in which a laser beam is guided both over the foaming areas and over adjoining areas to be discolored in order to produce the discolored contours. The laser beam can have a width which is greater than the width of the foaming areas, so that the laser beam projects beyond the foaming areas and discolored contours can be generated on both sides of the foaming areas. In this embodiment, the discolored contours extend directly to the foamed relief structure. Since these can not be discolored or a previously existing discoloration 'at least partially disappears when the plastic material foams up, the discolored contours have a boundary which corresponds to the inverse boundary of the relief structure. Experience has shown that the latter is irregular or frayed due to the foam structure.

Preferably, the laser for generating the foamed relief structure is vectorially controlled and the laser radiation is applied quasi-continuously. brought. In order to produce the discolored contour, the laser energy is expediently applied in a screened manner in a pointwise manner by operating the laser in a pulsed mode. To generate the relief structure, a suitable web guide of the laser can be provided as part of the vectorial control. For example, in order to obtain a controlled, modeled energy input, the laser can follow the lines of a grid, in the course of which the laser beam is guided several times over the crossing points of the grid. Alternatively, both the foamed relief structure as well as the discolored contour can be applied by a controlled grid operation, in which case the laser parameters are switched between the two processing steps.

The two processing steps of producing the discolored contour and the production of the foamed relief structure can advantageously be carried out on a single processing station, wherein the laser can be guided twice over the card in correspondingly different settings. A great advantage of this embodiment is that the complicated positioning of the card must be made only once.

The process according to the invention can be carried out on inexpensive, easily processed plastic material, such as, for example, PVC or polyester, in particular in the form of PET or PETG. The person skilled in the art knows how the energy must be introduced into the plastic material, for example, how the laser has to be matched in terms of its power, its wavelength and / or its operating mode to the plastic material used, in one case to foam the plastic material lead and in the other case lead to a discoloration of the plastic material. The invention will now be described by way of example with reference to the accompanying drawings. Show:

FIG. 1 shows an identification card designed according to the invention;

Figure 2 is a schematic sectional view of a contoured relief structure;

FIGS. 3a, b show a comparison of a conventional relief structure with a relief structure formed according to the invention;

FIG. 4 schematically shows a basic principle of the method according to the invention, in which a foamed relief area is surrounded by a discolored contour area;

FIG. 5 schematically shows an alternative basic principle of the method according to the invention, in which a larger area of contour area is superimposed overlapping a smaller relief area;

FIG. 6 schematically shows a basic principle of a further embodiment of the method according to the invention.

FIG. 1 shows an identity card 1 with a relief structure 3 contoured according to the invention and further inscriptions 5 and illustrations 7.

The ID card 1 has at least one plastic card surface on which one or more tactile symbols are formed. Symbols are understood to mean alphanumeric characters as well as graphic shapes and patterns in general. The tactility of the symbols becomes achieved by forming a relief structure. The symbols are divided into a central area and a border area. In the central area, the relief structure is formed. It consists of foamed plastic and has the inherent color of the plastic or at most has a slight discoloration compared to the intrinsic color. The edge region is flat to the map surface and compared to the intrinsic color of the plastic clearly discolored, so that the relief structure is contoured.

FIG. 2 shows a sectioned relief structure 3 in section. In addition to the foamed relief structure 8, which forms the central area of a symbol, are discolored areas which lie in the edge region of the symbol and form a contour 9 around the foamed relief structure 8. To produce the foamed relief structure 8, the laser is guided along a first path which traces the central regions of the symbols. To generate the contour 9, the laser is guided along a second path, which is derived from the first. The order of production of foamed relief structure 8 and contour 9 is freely selectable ..

The illustrated relief structure 3 was generated experimentally with a brand FOBA DP20GS laser, on the one hand, on a card 1 made of PETG, the laser being operated with a diode current of 28A and a frequency of 55 kHz. To produce the foamed relief structure 8, the laser was moved at a web speed of 7000 mm / s along the lines of a grid formed by three lines intersecting at 45 ° and 90 °, respectively; the line spacing was 0.07mm. To produce the discolored contour 9, a dot density of 465 dpi was set. On the other hand, with the same laser, the relief structure 3 was produced on an identification card 1 with a PVC core on which a cover layer made of a mixture of PET and PC was applied. With this card, foamed relief structure 8 and discolored contour 9 were both generated in gerereus operation. The laser was operated with a diode current of 26A and a frequency of 55 kHz. In order to produce the foamed relief structure 8, a dot density of 500 dpi was used, and to create the discolored contour 9 a dot density of 465 dpi was set. An enlargement of the contoured relief structure 3 is shown in FIG. 3b. Compared to a conventional relief structure (FIG. 3 a), the contoured relief structure 3 according to the invention is visibly easier to see visually.

The path control of a laser which can be used to produce the discolored contours 9 presents a particular challenge in the production method according to the invention. In particular, the path traveled to produce the foamed relief structure 8 can not simply be repeated. In order to arrive at a path control suitable for generating the contour 9, four exemplary solutions are proposed:

(A) A sample card with a foamed relief structure 8 is produced and then measured geometrically. From the measured values, path control data for the contour 9 are generated. The method gives very good results, but is expensive.

(b) Path control data for generating the contour 9 are computationally generated from the path control data for generating the relief structure 8, for example by adding an amount taking into account the width of the foamed relief structure 8 to the existing control data. The Method requires in order to provide optically good results, very complex algorithms and therefore is preferably suitable when only one consisting of a few simple symbols contoured relief structure 3 is to be formed.

FIG. 4 shows a region 11 to be foamed, within which a laser beam is traversed following a path. The properties of the laser beam are chosen so that energy is supplied to a card surface material such that it forms a foamed relief structure. On the basis of the dimensions of the area 11 to be foamed, control data for generating a contour line 13 are calculated. The laser is then adjusted in its properties so that it introduces energy into the card surface material such that it turns black. The laser beam is directed along the calculated contour lines. The result is a black-framed relief structure 15.

(c) If the card surface is made of a plastic which can not be discolored once it has been foamed by laser action, the width of a discoloring laser beam is made wider than the width of a laser beam used to form the foamed relief structure. In this case, the web used to produce the foamed relief structure 8 can be easily traced. The edge regions of the symbols projecting beyond the foamed relief structure 8 are then discolored in a contour-like manner, so that the contour 9 is formed, while the foamed relief structure 8 itself can not be inked or at most slightly colored.

FIG. 5 shows an example of a superposition of a relief structure 21 with a larger-area contouring structure 23. Both structures are in one One-line character set executed. This results in the outline-shaped relief sign 25th

(d) In order to produce the contour, the web used for the production of the foamed relief structure 8 is repeated several times, the web being displaced by a certain amount at each repetition to the original web used for the production of the foamed relief structure 8. The offset is preferably in the symbols associated main directions, typically in + x, -x, + y, -y direction.

Figure 6 shows an example in which a wider, "richer" character 33 is generated from a first pattern 31 by displacing the pattern as used to create the relief structure 31. This fatter character 33 is used to generate trajectory data used by the laser during the blackening and superimposed on the foamed relief structure 8. This results in a black outlined relief sign 35. By a suitable definition of the offset, such as omitting a main direction, a similar shadow effect can be achieved, as shown in Fig. 3b is shown.

While maintaining the basic approach to produce a contoured relief structure 3 on a plastic card by by means of a laser beam applied in two different energy modes in one step, a foamed relief structure 8 and in a further step, a surrounding, discolored contour 9 is generated, which allows Solution according to the invention a number of other modifications. Thus, in addition to the expressly mentioned also other plastic materials into consideration, which can be foamed and discolored. Furthermore, the specified processing parameters can be varied in order, for example, to have higher foamed relief structures 8 or to achieve a greater processing speed. Of course, the parameters also depend on the laser actually used and the purpose of the contoured relief structure 3. The solution according to the invention is not limited to identity cards, but is equally suitable for plastic cards with a different function and with arbitrary formats for telephone cards, entrance tickets or gift cards.

Claims

Patent claims

First identification card (1) with at least one plastic card surface, which has at least one tactile symbol with a relief structure (8), characterized in that the at least one symbol has a central and an edge region, wherein the relief structure (8) in the center is formed of foamed plastic and has the inherent color of the plastic, and which at least partially has a discoloration on the edge region which adjoins the relief structure (8), so that the relief structure (8) is at least partially offset by a contour (9). made of hardened plastic.

2. ID card according to claim 1, characterized in that the relief structure (8) is completely surrounded by the contour (9).

3. ID card according to claim 1 or 2, characterized in that the contour (9) has a uniform width.

4. ID card according to one of claims 1 to 3, characterized in that the relief structure (8) is not discolored.

5. ID card according to one of claims 1 to 4, characterized in that the foamed plastic of the relief structure (8) and the discolored plastic of the contour (9) have the same plastic material.

6. ID card according to claim 5, characterized in that the plastic material comprises PVC or polyester.

7. ID card according to claim 5, characterized in that the plastic material comprises polycarbonate or a mixture of polycarbonate with PVC or polyester.

8. A method of making at least one symbol on a badge (1) having a surface of a plastics material which has the property of increasing its volume by foaming when energized in a first energy delivery mode and changing color upon energization in a second energy delivery mode, comprising the step of: generating a frothed relief structure (8) on the badge (1) by applying energy by means of a laser in the first energy delivery mode to the central region of the at least one symbol, the laser moving along a first trajectory across the central region of the symbol becomes; and characterized by the additional step of: generating discolored contours (9) in the periphery of the symbol around the foaming regions by applying energy by means of a laser in the second energy delivery mode, the laser being guided along a path derived from the first.

9. The method according to claim 7, characterized in that when generating the foamed relief structure (8) and when generating the discolored contours (9), the energy is supplied in each case by irradiation with a laser beam.

10. The method according to claim 9, characterized in that the laser beam is controlled raster, wherein the energy input is pointwise.

11. The method according to claim 9, characterized in that in the step of generating discolored contours (9), the central areas are not irradiated with the laser beam.

12. The method according to claim 9, characterized in that the point density of the laser beam in the step of generating the foamed relief structure (8) is increased relative to the point density for producing the discolored contour (9).

13. The method according to any one of claims 9 or 10, characterized in that the laser beam in the step of generating the foamed Re- structure (8) vectorially controlled.

14. The method according to any one of claims 9 to 13, characterized in that the step of generating the discolored contour (9) and the step of generating the foamed relief structure (8) are performed with the same laser beam.

15. The method according to any one of claims 9 to 14, characterized in that the plastic material comprises PVC or polyester.